Blohm & Voss outboard tail projects (origins and descendants)

Me neither, certainly not maximum deflection. Maybe some pilots can weigh on this, but typically you get more drag than lift at the higher deflections; moderate deflections are used instead. My ballpark guess: 15 degrees?
 
Probably a modest deflection of around 15-25 degrees, but that would have been one of the unknowns to be quantified during flight testing. All the WWII German jets suffered takeoff issues due to engine thrust invariably being less than anticipated, with swept wings having the worst low-speed handling qualities. I can't recall which designs exactly, but at one point B&V investigated RATOG style strap-on booster rockets for takeoff. Without such rockets, a long takeoff run would certainly have been necessary and flap angle would have been a careful compromise between drag and lift.
I also think that scepticism over theoretical shortcomings needs to be carefully judged: no doubt small things would have changed during the detailed design and development work (which was barely begun), but the wing had been well enough researched and Vog't team on the whole turned out fundamentally sound, practical designs.
 
steelpillow said:
The Ae 607 delta is at best a red herring, it has zero provenance as far as B&V are concerned.
Click to expand...

I was wrong there. Dan Sharp has unearthed a contemporary copy of the original drawing. The B&V drawing office allocated an Ae number to each drawing and this particular drawing has no Project reference. But it is not really an outboard tail type, more a compound delta and is discussed elsewhere on this forum.
 
And here is a likely successor to the B&V series, Sud-Est (SNCASE) patent FR923549A from 1946/7.
It shows far less understanding of the aerodynamic and structural subtleties of the layout, being primarily concerned with positioning outside the main wake. The option of attaching the fins as endplates to the outboard tailplanes echoes contemporary practice with twin-fin designs but in this context is likely a novel invention, I never saw reference to it in any B&V source. They also suggest stuffing the booms with undercarriage, fuel tanks or even engine paraphernalia.
Breguet had been working on the BV 144 transport (see elsewhere) which was unrelated to the advanced jet programme and some of their design staff had visited their counterparts at B&V in Hamburg. The British had secretly hoovered up a lot of B&V material and shared it only with the Americans and French. Given the timing, it seems unlikely that Sud-Est invented it independently, but there is no hint as to whether Sud-Est picked up on some of the British-circulated material or might have been passed their information via Breguet. The implication of wingtip-mounted engines also echoes some well-known B&V project studies.
Thanks to inveterate twin-boom addict Tophe, of the What-If modellers forum, for tipping me off about this.
 

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Another threaderrection here...

Does anyone have some official documentation on the B+V P.209.01 they'd be willing to share? I have Justo Miranda's RD#15, and I'm quite familiar with Luft'46.com, but neither source gives any original drawings, nor do they list comparable dimensions. All I know for certain is the powerplant, the armament, the wing sweep (not sure if it pertains to the apparent plan sweep or the true sweep relative to the wing), that it had a span of greater than 10m and was less than 8m in length. This really isn't a lot of data!

One thing that I'm particularly interested in is the undercarriage assembly. The wing is generally described as being unburdened with the extra structure required by the landing gear, and was thus able to accommodate a large, unobstructed volume for fuel. However, where the undercarriage would need to retract looks like it would compromise the strength of the wing box or center fuselage in general. Or rather, this looks like it would be the case if the wheels stay in the vertical when tucking up into the fuselage, like many German designs from this period are want to do. This is a problem as fuselage side space is at a premium in this design, with the sides holding onto the cannon and the ammunition boxes. Is it possible the undercarriage made a 90 degree rotation to fit horizontally into a pair of deep wells in the forward fuselage?
 
Dan Sharp has published a couple of bookazines which include what he believes to be the only known original drawing of the P.209.01.

Originally reproduced in: Dan Sharp; Luftwaffe: Secret Jets of the Third Reich, Mortons 2015, but that can be difficult/expensive to get hold of. He published a smaller image of it in: Dan Sharp; Luftwaffe: Secret Wings of the Third Reich, Mortons 2017, which is easier to find. If I can find my flippin' camera I'll upload a snapshot.

It shows the main u/c retracting forwards and upwards, angled slightly to fit into the fat mid-section of a Me 262 style triangular fuselage. Naturally it straddles the engine air intake. But unusually this does not pose any structural problem. B&V were experts in welded sheet steel fabrication. The air intake, cockpit armour and wing and engine mounts were formed from a single steel fabrication. The outer framework and skinning were non-structural and large areas of panel could be removed for ease of maintenance.
The main wing structure was a torsion box running from the wing leading edge back to approx. 1/3 chord. Because the wing was swept, the CG lay well aft of the fuselage attachment point and, with a tricycle undercarriage, the main undercarriage hinges were ever further back. So the wheels slipped up snugly just behind the wing box. That too was sheet steel and doubled duty as an armoured fuel tank, another B&V speciality.
 
This is what the P 210 looked like. There was only one version of it and this is the only known drawing of it.

P 210 side.jpg
P 210 canopy frame.jpg
Blohm & Voss P 210.jpg
 
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Sadly, while the project description report 'Kurzbeschreibung BV P 210 und P 211 Jäger mit BMW 109-003' gives a table of weights for both types, it doesn't give dimensions in the text - these would presumably have been given on the drawings. But the drawings aren't included. Therefore, the only known verifiable source is the British intelligence report German Aircraft: New and Projected Types of January 1946, which took drawings from numerous original German sources and compiled them together.
It's possible that the reason why the project description no longer has its drawings is because Horace 'Rex' King, the guy who compiled 'New and Projected', simply removed them from it so he could use them for his own report.


P 210 weights.jpg
 
Thank you again for more original drawings. It's remarkable what reproduction drawings miss in comparison, even when they're well done and intentioned. Justo Miranda included a nice P.210 Volksjager drawing in RD#15, but strangely did not include any project description. I never quite understood that.

I think one of my previous posts might have walked off somewhere. If it did, please let me re-iterate that you chaps are amazing!
 
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